The pelvic floor muscles enclose the vagina and the abdomino-pelvic cavity. These muscles support the pelvic organs and control the close and release of their outlets. If the support and control mechanisms of the pelvic floor muscles are compromised pelvic organ dysfunction can result.
Muscle is generally made up of two types of fibres; the type I slow twitch fibres, which act for longer periods, and the type II fast twitch fibres which contract quickly for rapid movement. The slow twitch fibres of the pelvic floor muscles act to support the lower internal organs and also to help the bladder retain urine for long periods. The fast twitch fibres provide extra support to retain urine during times of stress, such as when lifting heavy objects, laughing, coughing or sneezing.
Pelvic organ dysfunction may occur when the pelvic floor muscles are stretched.
Many circumstances can result in the pelvic floor muscles becoming over-relaxed or stretched, but pregnancy and childbirth are the most common cause. Obesity, hysterectomy, bowel disorders, and other medical conditions can also affect the functioning of the pelvic floor muscles. Even in otherwise healthy women, factors such as lifestyle, aging, and hormonal changes can have a negative effect.
Weakened pelvic floor muscles may lead to urinary incontinence. To urinate, the muscles surrounding the bladder contract and squeeze the urine out through the urethra. The urethra passes through the pelvic floor muscles supporting the bladder, bowel and uterus. If the pelvic floor muscles are weak they are unable to close off the urethra effectively, leading to leakage of urine. Stress incontinence is urine loss that occurs when there is increased pressure in the abdomen. This commonly occurs during coughing, sneezing, laughing, lifting and exercise. Urge incontinence is the loss of urine associated with a sudden strong desire to urinate that cannot be postponed.
Urge incontinence is generally triggered by certain events such as the sound or sensation of running water, sudden exposure to cold or fumbling with the front door keys trying to open the door. Urge incontinence has also been described as overactive bladder.
Some women suffer from mixed incontinence and experience a combination of both symptoms.
If the pelvic floor muscles are sufficiently stretched or weakened a woman may experience pelvic organ prolapse. In pelvic organ prolapse the organs of the pelvis may drop down out of their normal position causing a feeling of pelvic pressure or heaviness in the pelvic region.
Pelvic support problems include cystocele, where the bladder is not supported properly; enterocele, where the small intestine is not supported properly; rectocele, where the rectum is not supported properly; uterine prolapse, where the uterus is not supported properly; and vaginal prolapse, where the vagina is not supported properly. In some cases pelvic organ prolapse requires surgery.
Furthermore, because many of the sensations experienced during sexual intercourse result from stimulation and contraction of the pelvic floor muscles, loss of tone of the pelvic floor muscles can also lead to a reduction in sexual responsiveness.
Damage to the pelvic floor muscles may also be associated with neural damage. In particular, pregnancy and childbirth can stretch the nerves connecting the pelvic floor muscles to the brain. If these nerves are damaged so that they cannot provide proper sensory feedback, the woman may not be able to coordinate the muscle contractions needed for urinary continence. Sexual enjoyment may also be decreased.
The pelvic floor muscles can be strengthened by regularly contracting and relaxing them. The most common form of pelvic floor exercises are known as Kegel exercises. Unfortunately, the women most in need of pelvic floor muscle training may have experienced stretching of the muscles and neural damage that prevents them from being able to properly sense the muscle contractions. Therefore, pelvic floor exercises may not be effective.
A number of devices have been developed the help exercise the pelvic floor muscles. These devices generally involve a portion that is inserted into the vagina, to provide resistance for the pelvic floor muscles to contract against. Examples of such devices are outlined below.
U.S. Pat. No. 4,241,912 teaches a device that has a section that is inserted into the vagina, and an outer flange and handle which prevent full insertion. The body of the device is shaped to fit into the vagina and is substantially rigid. Because the device is not fully insertable, it can only be used in limited situations.
U.S. Pat. No. 4,895,363 teaches a series of weighted cones that are inserted into the vagina. Once inserted the patient contracts the pelvic floor muscles and attempts to prevent the weighted cones from falling out. Because the exercise only involves the contraction and holding of the pelvic floor muscles, only the slow twitch muscles are targeted. The exercises can also only be performed in limited circumstances.
U.S. Pat. No. 5,931,775 teaches a device consisting of a handle portion and a cylindrical projection that has a solid inner wall and an outer compressible sleeve. The cylindrical projection is inserted into the vagina and the compressible sleeve provides resistance against which the pelvic floor muscles can be contracted. The handle portion also means that it cannot be fully inserted into the vagina, limiting where and how the exercises are performed.
WO 01/37732 teaches a device for both measuring and exercising the pelvic floor muscles. It includes a probe having a pressure sensor and vibrator, linked to an external microprocessor. The device is used by inserting the probe into the user's vagina and firstly measuring the maximum highest contraction value achieved when the user contracts the pelvic floor muscles. Secondly, the vibrator is activated during further contractions of the pelvic floor muscles in accordance with a predetermined relationship between the strength of the pelvic floor contraction and the highest value. The device according to WO 01/37732 is expensive and difficult to use. The external microprocessor limits or restricts the positions that exercises can be performed in.
WO 01/30457 teaches a number of small devices for exercising the pelvic floor muscles. Resistance in the devices is achieved either by springs, fluids of compressible material. None of the devices taught in WO 01/30457 are completely insertable. This means that they can only be used in private situations and cannot be linked to functional training where most stress incontinence occurs, ie, when the user is walking, running or coughing etc.
WO2005/070504 describes a device having an indicator that protrudes from an end of the device as the muscles are contracted. Accordingly, the device can only be used in limited situations, and cannot be used for extended periods.
U.S. Pat. No. 6,394,939 describes an exercise device having a shaft portion, a head portion at one end and a gripper at the other end. At least a portion of the shaft is compressible. The gripper is a rectangular body, which would prevent insertion of the entire device, limiting where and how the exercises are performed.
U.S. Pat. No. 5,483,832 describes a device for monitoring the contractibility of the pelvic floor muscles. The device has a probe with a first and second end and a number of chambers defined by an elastically deformable membrane. The device is connected to a measurement display device by a measurement line, limiting where the device can be used.
WO 00/41772 describes a device having an elongate body that has a reduced cross section in its middle section. This device cannot be fully inserted into the vagina, limiting where and how the exercises are performed.
U.S. Pat. No. 7,001,317 describes a Kegel exercising device. The device has a first sphere and a second sphere with an intermediate portion. The device is cast from surgical steel. One end of the device is inserted vaginally, and the other end of the device is inserted rectally which may be off-putting to some women.
With the devices above, the user may not be able to properly sense the pelvic floor muscles contracting and relaxing. Consequently, the user may be unsure as to whether she is performing the exercises correctly.
In this specification where reference has been made to patent specifications, other external documents, or other sources of information, this is generally for the purpose of providing a context for discussing the features of the invention. Unless specifically, stated otherwise, reference to such external documents or such sources of information is not to be construed as an admission that such documents or such sources of information, in any jurisdiction, are prior art or form part of the common general knowledge in the art.
It is intended that reference to a range of numbers disclosed herein (for example, 1 to 10) also incorporates reference to all rational numbers within that range (for example, 1, 1.1, 2, 3, 3.9, 4, 5, 6, 6.5, 7, 8, 9 and 10) and also any range of rational numbers within that range (for example, 2 to 8, 1.5 to 5.5 and 3.1 to 4.7) and, therefore, all sub-ranges of all ranges expressly disclosed herein are hereby expressly disclosed. These are only examples of what is specifically intended and all possible combinations of numerical values between the lowest value and the highest value enumerated are to be considered to be expressly stated in this application in a similar manner.
It is an object of at least preferred embodiments of the present invention to provide a device that is suitable for insertion into the vagina to support the pelvic floor muscles or to provide satisfactory resistance for exercising the pelvic floor muscles, or that at least provides the public with a useful choice.